Aspects of the disclosure relate to computing technologies. In particular, aspects of the disclosure relate to mobile computing device technologies, such as systems, methods, apparatuses, and computer-readable media for improving orientation data.
Increasingly, computing devices, such as smart phones, tablet computers, personal digital assistants (PDAs), and other devices, include touch screens, accelerometers, magnetometers, gyroscopes, cameras, proximity sensors, microphones, barometers, and/or other sensors that may allow these devices to capture motion and orientation and/or other sensed conditions as a form of user input. Application developers and users for devices are finding new and novel ways of utilizing the motion and device orientation associated with the devices. Vast array of sensors have become common on most devices.
Sensors such as accelerometers, gyroscopes, magnetometers aid in determining the motion and orientation of the device. An accelerometer measures acceleration forces including gravity. A gyroscope measures relative orientation of a device, for example based on the principles of conservation of angular momentum. A magnetometer is an instrument used for measuring the direction and strength of a magnetic field. Fusion of these sensors may allow for smooth and accurate characterization of the motion and orientation of a device.
At a device, at a hardware, firmware and software level, various sensor fusion techniques are used to improve the results from these sensors. Sensor fusion is the combining of sensory data or data derived from sensory data from disparate sources such that the resulting orientation information is in some sense more accurate, more complete, or more dependable than would be possible when these sources were used individually.
Fusing sensor inputs present a unique set of opportunities for increasing power and time efficiency of the device system without compromising accuracy for determining the motion and orientation of the device. However, fusing sensor inputs may also present a unique set of challenges for system integration and limit certain improvements. For instance, sensors may provide information in different formats than what is expected or utilized by other elements or systems. For example, some operating systems, applications, and/or other forms of hardware may utilize specific formats of measurements from the sensors as input, for example for standardization purposes. Therefore, not only is it beneficial to increase the speed and accuracy of sensor data or measurements, but it is also beneficial to generate such data or measurements in an appropriate format that is consumable by the higher layers in the device.
Furthermore, many devices such as cameras expect quick response from the sensors for enabling applications such as perspective compensation in camera images. Such applications have tight delay requirements along with high accuracy needs. Known filters used for filtering out noise may comprise static first order filters that have low performance and cannot quickly adapt to the changing noise in the operating environment of the sensors.
Aspects of the disclosure provide more convenient and effective ways of deriving orientation data.